Method of constructing roads



Dec. 28,1926. 1,612,530

M. L. 0 NHL METHOD CONSTRUCTING ROADS Filed Dec. 7 1 5 gwugntop W Ma i;

l atented Dec. 28, 1926.

UNITED STATES PATENT OFFICE.

MURT L. O'NEIL, OF SVJ'ISSHOIYIE, OREGON, ASSIGNQR T0 ROBERT J. O'NEIL, OF COCONINO COUNTY, ARIZONA.

METHOD or consrnno'rme ROADS.

Application filed December '7, 1925. Serial No. 73,915.

This invention relates to road construction and has for its object to provide a method of construction by which the material forming the road, which may be gravel, crushed stone or the like, will be a uniform mixture of fine, coarse, and intermediate grades of the material throughout the length, breadth,

and depth of the road bed, rather than a patch of coarse material, a patch of fine material and a patch of medium material indiscriminately placed.

In the practical construction of roads with gravel or crushed stone it has been found that no matter how much care has been taken in handling the material, some loads will contain considerably more of fine gravel than of coarse gravel and vice versa, while some loads will consist of practically all fine or coarse material. Heretofore it has been the practice to dump these ununiform loads on the sub-grade at spaced intervals and spread them thereon to a depth of six or eight inches depending on the thickness required in the completed road. After being thus spread the gravel is rolled and compacted in the usual manner.

Obviously, a road formed as just described would be of little service for the reason that the portions thereof which are formed of the loads of relatively fine material will soon be more or less destroyed by winds which will blow the material away in the form of dust, and will also be formed into ruts and depressions by the traflic, whereas those portions of the road which are formed of the coarse material will stand up much better, thereby creating a series of ridges and depressions throughout the length of the road. Even those portions of the road containing the coarse material will deteriorate in dry weather, however, due to the absence of the fine material which should ordinarily act as a binder for the larger aggregates.

The present invention provides a method for constructiong a gravel road which is just as simple as that hereinbefore described and yet which will insure that the finished road will be of uniform mixture throughout, thereby avoiding the objections to gravel roads as heretofore constructed.

In the following detailed description and claims it is to be understood that the word gravel is used m a generlc sense and 18 mtended to. include crushed stone and other similar material as well .as gravel.

In the drawings: 1

Figure 1 shows a longitudinal section through .a ridge forming the first step :of my improved method; and

Figure 2 is a similar view of a completed road.

According to the present method and as shown in Figure l of the drawings the first load of gravel is strewn longitudinally of the subgrade'in a relatively thin layer for a distance of one hundred feet more or less. The next layer is then strewn along in the same manner on top of the first layer, but

this second layer beginsat a point in advance of the beginning of the first layer. and terminates at an equal distance be: yond the terminal of the first layer. The distance between the terminals of adjacent layers may be varied as desired but should ordinarily be about twenty feet.

These superposed layers of gravel are continued until a ridge of proper thickness is built up, and if a road of unusual width is desired two such ridges may be built in parallel relation. The ridge which isindicated in Figure 1 by the reference numeral 1 is composed of a number of shingled layers as just described. Several of the layers are designated by the numerals 2, 3, 4, 5 and 6, and in order that the invention may be clearly illustrated the layers 2, 3 and 6 are shown as loads of fine material while the layers 4 and 5 are shown as loads of coarse material.

After the ridge has been formed as shown in Figure 1 it is bladed or otherwise spread to the proper width and in this step of the process a large percentage of thelarger aggregates are caused to descend to the road bed as described in my prior Patent #1,489,783, dated April 8, 1924. In this way the ideal gravel road; namely, one in which the coarser aggregates form the bottom of the road, the intermediate sizes of gravel form the intermediate portion of the road, and a fine gravel forms the surface of the road, is approximated.

From the foregoing description taken in connection with the accompanying drawings it will be apparent that I have devised an extremely simple method by which gravel roads may be constructed so that when completed a substantially uniform mixture of gravel will be secured throughout the length and breadth of the road, but with a large percentage of the larger aggregates toward the bottom of the road; and that this result is accomplished irrespective of the fact that certain of the loads of material may consist entirely of line gravel and other loads may consist entirely of coarse gravel.

In accordance with the patent statutes I have described what I now believe to be the best embodiment of the invention, but I do not Wish to be understood thereby as limiting myself, or the scope of the invention, as many changes and modifications may be made Without departing from the spirit of the invention; all such I aim to include in the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. A step in the method of constructing gravel roads which consists in forming a ridge longitudinally of the subgrade by strewing the loads of gravel in thin layers longitudinally of the subgrade, the layers overlapping throughout a considerable portion of their length and the beginning of each layer being in advance of the beginning of the preceding layer.

2. A step in the method of constructing gravel roads which consists in forming a ridge longitudinally of the subgrade by strewing the loads of gravel in thin layers longitudinally of the subgrade, the layers overlapping throughout a considerable portion of their length and the beginning or" each layer being in advance of the beginning of the preceding layer, and the terminal of each layer being beyond the terminal of the preceding layer and in contact with the subgrade.

8.- The method or" constructing gravel roads which consists in first forming a ridge longitudinally of the sub-grade by strewing the loads of material in thin superposed layers longitudinally of the sub-grade, and then spreading said ridge to the proper width, whereby a large percentage of the larger aggregates are caused to descend to the road bed.

4:. The method of constructing gravel roads which consists in first forming a ridge longitudinally of the sub-grade by strewing the loads of material in thin layers longitudinally of the sub-grade, the beginning of each layer being in advance of the be inning of the preceding layer, and then spreading said ridge to the proper width, whereby a large percentage of tie larger aggregates are caused to descend to the road bed.

MURT L. ONEIL. 

